Chaos-MCP is an MCP stdio server that runs isolated mutation testing against a target codebase to expose gaps in its test suite. It wraps four language engines — StrykerJS (TS/JS), cosmic-ray (Python), cargo-mutants (Rust), Infection (PHP) — and exposes three tools: audit_code_resilience, triage_test_coverage, and estimate_audit.

Quick Install

Copy the config for your editor. Some servers may need additional setup — check the README.

Add to claude_desktop_config.json:

{
  "mcpServers": {
    "chaos-mcp": {
      "command": "npx",
      "args": [
        "-y",
        "AraneaDev/Chaos-MCP"
      ]
    }
  }
}

README Excerpt

> On-demand micro-mutation sandbox for AI test verification — maps holes in unit tests by running isolated mutation testing via the Model Context Protocol. > **Pre-release / in active development.** Chaos-MCP is **not yet published to npm**. The source is public on [GitHub](https://github.com/AraneaDev/Chaos-MCP) — install from source (see [Installation](#installation)). Any `npm install -g` / `npx` commands in this README describe the planned published experience and do not work yet.

Tools (20)

approxbaselineconcurrencydefaultFileConcurrencydefaultMaxFilesdefaultMaxSurvivorsdefaultSeverityFloordefaultTimeoutMsdiffBasedryRunenrichexactfileConcurrencyfilePathharden_fileignorePatternsincrementallineScopemaxFilesmaxSurvivors

Topics

mcpmodel-context-protocolphppythonrusttestingts

Chaos-MCP

Quick Install

README Excerpt

Tools (20)

Topics

Related Code/Dev Tools Servers